Central Air Conditioning Repair


Central Air Conditioning Repair should be done by qualified personnel. Over time, parts of the air conditioning system may need replacement, cleaning or re-greasing. By looking at the symptoms such as noisy compressor, noisy fan assembly, failure of compressor to start or main circuit breaker cut-off, you will be able to narrow down the possible root cause of the problem.




Some of the symptoms and possible root cause of the components failure are as listed below.

Compressor Noisy
Fan Assembly Noisy
Electrical Parts Noisy
Other Parts Noisy
Compressor Fails To Start
Condenser Fan Motor Fails To Start
Compressor and Condenser Fan Motor Fail To Start
Compressor Internal Thermostat Cut-Out
Compressor Overload Relay Cut-Out
Condenser Fan Motor Overload Cut-Off
Main Circuit Breaker Cut-Off


Compressor Noisy
  • Oil compression
  • Liquid compression
  • Valve of the compressor is broken
  • Compressor is wobbling or moving unsteadily from side to side
Fan Assembly Noisy
  • Fan motor bearing could be damaged
  • Fan belt has been adjusted too tight or too loose
  • V-belt has worn out on one of its side
  • Drive and pulley are not in the same plane causing wobbling
Electrical Parts Noisy
  • Loose wiring connection
  • Fan motor magnetic switch is not working
  • Compressor magnetic contactor is not working
  • Dirt or other impurities on magnetic contactor surface
Other Parts Noisy
  • Rattling of piples
  • Bolts or screws that are loosed
  • Improper installation
  • Foundation of the unit is weak
Compressor Fails To Start
  • Wiring not connected
  • Wiring connection is wrong
  • Wiring connection is loose
  • Wrong thermostat setting or themostat is not working
  • Magnetic coil of the compresor contactor malfunction
Condenser Fan Motor Fails To Start
  • Wiring connection is wrong
  • Loose wiring connection
  • Interlocking wiring is disconnected
Compressor and Condenser Fan Motor Fail To Start
  • Fan motor contactor magnetic coil malfunction
  • Wiring connection loose or disconnected
  • No power supply
  • Main fuse blown
  • Earth leakage circuit breaker tripped
  • Wrong wiring connection
  • Wiring is undersized
  • Power supply disconnected
Compressor Internal Thermostat Cut-Out
  • Compressor valve is broken
  • Undercharge of refrigerant
  • Ineffective compression of compressor
  • Undervoltage power supply
  • Phase failure in 3-phase motor
Compressor Overload Relay Cut-Out
  • Wrong wiring connection, improper use of wiring size or loose wiring connection
  • Compressor wobbling unsteadily
  • Lack of lubrication in the compressor rotating parts
  • Undervoltage of power supply
  • Compressor motor malfunction
  • Phase failure in 3-phase compressor motor
  • Compressor overload malfunction
  • Compressor magnetic contactor malfunction
  • Wrong setting of compressor overload
Condenser Fan Motor Overload Cut-Off
  • Loose wiring connection, wrong wiring connection or undersized wiring
  • Phase failure if the motor is 3-phase motor
  • Undervoltage power supply
  • Malfunction of fan motor overload relay
  • Wrong overload relay setting ampere
  • Fan motor malfunction
  • Bearing of fan motor has worn out
  • Fan motor magnetic contactor switch malfunction
Main Circuit Breaker Cut-Off
  • Loose wiring connection or undersized wiring
  • Compressor wobbling unsteadily
  • Compressor rotating parts locked due to lack of lubrication
  • Phase failure if motor used is 3-phase motor
  • Undervoltage power supply
  • Malfunction of compressor motor
  • Impurities on magnetic contactor surface





Go To Central Air Conditioning Troubleshooting Part 2 


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